According to 2014 Tax Year 1040 Quickfinder Handbook 4-11, and 4-12, foor the purposes of federal tax requirements of the IRS, a Qualifying Relative is a person who is not a qualifying child of anyone else and who also meets the following 3 tests with respect to the taxpayer. (IRC 152 (d))
1 - Member of household or relationship
2 - Gross Income
3 - Support
Two of our young adult children still being supported by us at home fail the Gross Income test of less than $3,950.
However, FAFSA appears to ask different questions and dependents differently with a different set of questions.